THE CONGRESS HALL, CLAPTON.
This structure, in Lynscott Road, Clapton, is the largest in the United Kingdom owned by the Salvation Army, and is held in peculiar estimation by Salvationists in consequence of its association with the training, carried on in adjoining buildings, of young men and women as officers of the Salvation Army in all parts of the world. Before "General" Booth secured the property it was occupied by the London Orphan Asylum, now at Watford. In place of a small chapel, which stood between the two wings, he erected the Congress Hall, which was inaugurated in May, 1882, and has a seating capacity of 4,500. It is open every evening in the week, and all day on Sundays, and is used for many of the special gatherings of the Army.
source: The Queen's London : a Pictorial and Descriptive Record of the Streets, Buildings, Parks and Scenery of the Great Metropolis, 1896